Various methods and devices for joining wall panels and forming corners are known. Forming interior corners of walls that are intended to provide a living space generally require a flush, smooth, aesthetically pleasing surface. Constructing and joining drywall and gypsum panels generally comprises process steps of taping and mudding. Drying time is required in order to finish the wall(s). Existing methods and devices for constructing living spaces and forming corners require considerable amounts of time and labor and are subject to various inaccuracies and opportunities for error.